Paint some cells black to create a continuous wall.
Number(s) in a cell indicate the length(s) of the wall in its surrounding cells.
If there is more than one number in a cell, there must be at least one white cell between the wall parts.
The wall cannot form any 2x2 blocks anywhere.

General discussion: Every rule should define the word "neighbourship". In most puzzles the neighbours are only the orthogonally adjacent cells; in Tapa also the diagonally adjacent cells are neighbours. Since orthogonal neighbourship is far more often used than general neighbourshi, the latter one should be explicitly mentioned. (Exclusion fo diagonal neighbourship is most often emphasized by "not even diagonally").

The problem with using the word 'surrounded', as I discovered in an interesting discussion back in my TP days, is that the edge and corner squares are not surrounded! I can't remember the precise circumstances where it cropped up, but it's one that has potential to confuse. Better to avoid!